Genes and Olympic performance: a co-twin study

An Olympic gold medalist in a 20 km competitive walking race and his identi cal twin brother, also an Olympic athlete in the same event but with inferi or performance, were tested in order to obtain some further insight into th e relative importance of genetic factors in modulating athletic excellence. Both twins had undergone the same strenuous, long-term training for 19 yea rs since the age of 15 under the guidance of the same coach. An assessment of their bio-behavioural profiles at 40 years of age, i.e. 7 years after th ey ceased training, revealed that intrapair differences were negligible in physiological attributes but divergent in personality traits measured. Resp ective values for the Olympic winner and his identical counterpart were as follows: Body mass index 23.2 and 22.7, cardiac mass index 85.4 and 84.4 g x m(2), squat jumping 25.3 and 27.3 cm, VO2 at running speed 9 km x h(-1) 3 3.1 and 33.6 ml x kg(-1) x min(-1), VO2 max 57.1 and 58.6 ml x kg(-1) x min (-1) (72.5 ml x kg(-1) x min(-1) for the Olympic winner at age 22 yrs), rea ction to anger 97 and 9 and anger expression 2 and 76 in percentile of the State-Trait Anger Expression Inventory. Findings suggest that although gene tic constitution and years of physical training are prerequisites for makin g an Olympic athlete, success may be largely influenced by personality trai ts.